Track runner bearing with a PA66 axial sliding and sealing ring on both sides. Improved crowned profile of the outer ring running surface

PPSKA

KR design cam follower, sizes 16 and 19, with a PA66 axial sliding and sealing ring on both sides, improved crowned profile of the outer ring running surface and a hexagonal recess in the head of the stud, no relubrication features

PPXA

Cam followers with PPA features except for the outer ring running surface, which has a cylindrical profile

Q

Optimized contact geometry and surface finish

Polymer ball bearing with components made of glass

QBC

Set of four bearings arranged tandem back-to-back <<>>

QBT

Set of four bearings arranged back-to-back and tandem <>>>

QCL7C

Bearing with very tight geometrical tolerances and high preload capability

QFC

Set of four bearings arranged tandem face-to-face >><<

QFT

Set of four bearings arranged face-to-face and tandem ><<<

QR

Set of four single row deep groove ball or cylindrical roller bearing matched for equal distribution of radial load

QT

Set of four bearings arranged in tandem <<<<

R

Flanged outer ring

Polymer ball bearing with components made of borosilicate glass

RF

Contact seal made of acrylonitrile-butadiene rubber (NBR), additional rubberized flinger, on one sde of the bearing

2RF

RF contact seal, on both sides of the bearing

RS

Contact seal made of acrylonitrile-butadiene rubber (NRB), on one side of the bearing

2RS

RS contact seal, on both sides of the bearing

RS1

Contact seal made of acrylonitrile-butadiene rubber (NRB), on one side of the bearing

2RS1

RS1 contact seal, on both sides of the bearing

RS1Z

Sheet steel reinforced contact seal of acrylonitrile-butadiene rubber (NBR) on one side and one shield on the other side of the bearing

RS2

Contact seal made of fluoro rubber (FKM), on one side of the bearing

2RS2

RS2 contact seal, on both sides of the bearing

RS5

Contact seal made of hydrogenated acrylonitrile-butadiene rubber (HNBR), on one or both sides of the bearing

2RS5

RS5 contact seal, on both sides of the bearing

RSH

Contact seal made of acrylonitrile-butadiene rubber (NBR), on one side of the bearing

2RSH

RSH contact seal, on both sides of the bearing

RSL

Low-friction contact seal made of acrylonitrile-butadiene rubber (NBR), on one side of the bearing

2RSL

RSL low-friction contact seal, on both sides of the bearing

RZ

Low-friction non-contact seal made of acrylonitrile-butadiene rubber (NBR), on one side of the bearing

2RZ

RZ low-friction non-contact seal, on both sides of the bearing

S

Matched bearings for an equal load distribution. The number preceding indicates the number of bearings, e.g. NK 50/25 TN/2S

Polymer ball bearing with components made of Stainless steel 1.4034

S0

Bearing heat stabilized for operating temperatures ≤ 150 °C (300 °F)

S1

Bearing heat stabilized for operating temperatures ≤ 200 °C (390 °F)

S2

Bearing heat stabilized for operating temperatures ≤ 250 °C (480 °F)

S3

Bearing heat stabilized for operating temperatures ≤ 300 °C (570 °F)

SB

SKF ConCentra ball bearing with shortened inner ring

SM..

Special grease, two numbers following identify the grease

/SORT..

Tolerance grade of needle rollers of a needle roller and cage assembly, the numbers following identify the actual limits in μm, e.g. /SORT-2-4